The US tops the charts for its involvement in the light-rail space, which in many respects is considered the most sustainable form of passenger transport. Light rail is considered to be an environmentally sustainable transit option thanks to its contribution to reducing air pollution, energy consumption and greenhouse gas emissions.
While walking and cycling are the most sustainable ways of getting around, light rail comes out on top among its high-occupancy passenger transport peers, which include rail, tram, bus and metro. Compared with buses especially, light rail can draw more people out of cars, releases no air pollution and, like heavy rail, obtains power from environmentally friendly sources such as electricity.
Since 2010, the US has seen 27 light-rail projects come to market for a total value of $35bn and length of 553km.
Light rail is also perceived to be particularly good in cutting other externalities beyond air pollution, including accidents, noise and congestion, water and soil pollution. While findings indicate that a light-rail presence affects environmental sustainability in varying degrees, they also show that it alone cannot significantly affect energy intensity, energy per capita, carbon dioxide (CO2) intensity and CO2 per capita.
Other factors, including light-rail transit ridership, come into play as they influence how light-rail transit affects the environmental sustainability in urban areas.
